The present invention relates to a system for inspecting exposure pattern data of a semiconductor integrated circuit (IC) device. More particularly, it relates to a system for inspecting exposure pattern data of a semiconductor IC device on the basis of exposure pattern data in an image data form.
Semiconductor integrated circuits (ICs) are generally manufactured by the following steps: logic design; pattern design; mask manufacturing; wafer process for manufacturing wafers; cutting wafer and assembling IC. The pattern design step involves: logic translation; circuit design; circuit analysis; pattern layout design; characteristics analysis; and modification of a pattern layout. The mask manufacturing process includes the steps of: reading coordinates from pattern layout design drawings; displaying the coordinates on a cathode ray tube (CRT), or plotting the coordinates by a plotter; testing and modifying data of the coordinates on the CRT or plotted drawings; producing original patterns by means of a pattern generator; producing master masks by means of a photo-repeater; and making working masks.
Automation of the above pattern design has been achieved by utilizing a Computer Aided Design (CAD) system. Pattern layout data produced by the CAD system is stored in magnetic tapes on the basis of predetermined formats by, for example, the CV Corporation, CALMA Corporation, etc. The pattern layout data defines only outlines, and accordingly, prior to the production of reticle patterns by actual exposure, the pattern layout data must be data-translated to produce exposure data, and the exposure data must be carefully inspected.
Systems for inspecting the exposure data are widely known, and an exposure data inspecting system is generally realized by using a general-purpose computer system and a program, such as DRACULA, SPICE, etc. The conventional exposure data inspecting system provides visual exposure data in a two-dimensional form and is produced from the data of the coordination system having, for example, the CALMA format on the CRT or the pattern. The displayed exposure data can be visually inspected by the operator.
The conventional exposure data inspecting systems, however, suffer many disadvantages, such as a low data processing speed, and accordingly, a low inspection efficiency, limitations of inspecting functions, and poor inspection accuracy, etc. These disadvantages will be described later, in more detail, with reference to specific examples.